Olympus Mons caldera in perspective

11 August 2004

This perspective view, taken by the High Resolution Stereo Camera (HRSC) on board ESA's Mars Express spacecraft, shows the complex caldera of Olympus Mons on Mars, the highest volcano in our Solar System.

Olympus Mons has an average elevation of 22 kilometres and the caldera, or summit crater, has a depth of about 3 kilometres. The data was retrieved during orbit 143 of Mars Express on 24 February 2004. The view is looking north.

The curved striations on the left and foreground, in the southern part of the caldera, are tectonic faults. After lava production has ceased the caldera collapsed over the emptied magma chamber. Through the collapse the surface suffers from extension and so extensional fractures are formed.

The level plain inside the crater on which these fractures can be observed represents the oldest caldera collapse. Later lava production caused new caldera collapses at different locations (the other circular depressions). They have partly destroyed the circular fracture pattern of the oldest one.

This perspective view of the caldera was calculated from the digital elevation model derived from the stereo channels and combined with the nadir and colour channels of the HRSC.